Anti-jackknifing couplings have been developed to prevent damage to articulated vehicles. Jackknifing is the accidental folding of an articulated vehicle such that it resembles the acute angle of a folding knife. One example of jackknifing occurs when a tow vehicle skids and a trailer pushes the tow vehicle from behind until the tow vehicle spins around and faces backwards. Typical causes for jackknifing include equipment failure, improper braking, or adverse conditions, such as an icy road surface.
One known anti-jackknifing device includes a pair of stop blocks extending from the trailer, which engage a pair of latch blocks extending from the tow vehicle. These rigid blocks prevent movement of the vehicle beyond a predetermined range of free articulation. However, it will be appreciated that the rigid blocks may fracture when the stop blocks impact the latch blocks under an initial impulse load. Also, the rigid blocks typically do not warn the driver of over-articulation of the vehicle.
Typical anti-sway hitches can include an array of complex linkages with helical springs for damping the swaying movement of improperly loaded trailers. These complex linkages can increase the time required for installation on vehicles.
It is therefore desirable to provide an anti-jackknifing hitch assembly having a simple construction that improves control of an articulated vehicle, provides feedback regarding trailer position, and prevents over-articulation of the vehicle.